The correct answer is: C. is widely used in industrial automation
A solenoid is a coil of wire that creates a magnetic field when an electric current is passed through it. This magnetic field can be used to attract or repel a metal object, such as a plunger. Solenoids are widely used in industrial automation, as they can be used to control a variety of devices, such as valves, switches, and motors.
Option A is incorrect because solenoids can be used in both AC and DC circuits.
Option B is incorrect because solenoids are not spring operated. The magnetic field created by the coil of wire is what moves the plunger.
Option D is incorrect because solenoids are not related to aneroids. Aneroids are devices that measure air pressure.
Option E is incorrect because solenoids are widely used in industrial automation.